The Prime Minister told Total Politics magazine that the coalition was the best way to get things done but "if that wasn't the case then we'd have to face the new circumstances in whatever way we should."
The Deputy Prime Minister will say: "He echoed exactly what both of us have always believed: this coalition has been remarkably radical; it still has work to do; and the best way for us to serve and improve Britain is by finishing what we started.
"I am absolutely committed to this coalition lasting until 2015 - as is the Prime Minister."
Claims that it was in either or both parties' interests to "prematurely pull the plug" were wrong, he will suggest.
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The department store chain said nearly 400 jobs would be lost as it grapples with the pressures facing the retail sector.
Consumer prices have rocketed by 58% since 2003, with the UK industry paying the biggest bills in Europe.
Friday will be a much calmer day for many, with the weather set to remain dryer with sunny periods and much lighter winds than on Thursday.